Module 3 MICR 271 Exam With Correct Actual Questions And Correctly Well Defined Answers.

Bacterial populations grow through which process - correct answer Binary fisison Binary fission begins with - correct answer with replication of the baterial chromosome as an individual cell grows During the binary fission, further cell growth leads to - correct answer an invagination of the cell wall until the separate daughter cells are pinched off Chromosome replication in daughter cells begins before they are separated for what reason? - correct answer This allows division of each daughter cell to occur soon after separating from the mother (With nutrients) Stages of binary fission in order - correct answer 1) Cell wall, membrane and overall volume are enlarged; chromosomes are duplicated. 2) Septum begins to form and chromosomes are pulled to opposite ends of the cell; components are randomly divided. 3) Septum is completely formed and the cell membrane begins to patch itself. 4) Daughter cells are divided. peptidoglycan - correct answer A protein-carbohydrate compound that makes the cell walls of bacteria rigid What prevents a cell from lysing due to osmotic pressure during the bacterial binary fission - correct answer cytoplasmic contents are continuously enclosed by a cell wall senescence - correct answer the natural physical decline brought about by aging After each fission event - correct answer one pole of a cell is made of older material, which can include damaged components senescence becomes damaged due to - correct answer Inherting old cell wall material at the "old" pole Inherting damaged DNA Inherting damaged proteins Activation of damage defense systems (M) rather than (G) The majority of damaged cellular components are inherited by - correct answer cells with "old" poles Which cell will outcompete the other in binary fission? - correct answer The "Daughter" lineage can divide more rapidly and will outcompete the slower growing Mother cells Anabolism - correct answer Building of components, such as proteins, DNA Catabolism - correct answer Breakdown of molecules to obtain Facilitated Diffusion: - correct answer Molecules move from an area of higher concentration to one of lower concentration by way of a carrier molecule. No energy is required. Primary Active Transport: - correct answer Nutrients are moved from an area of flow concentration to high concentration using energy from ATP. Secondary Active Transport: - correct answer The movement of one molecule down its concentration gradients to facilitate the movement of another molecule across the cell membrane. No energy required. Group Translocation: - correct answer Molecules are transferred across the membrane into the cell into conjunction with chemical modification. Iron Uptake: - correct answer Several mechanisms exist, particularly the formation of complexes with sliderophore or through the uptake of heme. What are the physical requirements for growth: - correct answer Temperature, PH, Water Availability, Pressure as well as Oxygen levels Why are oxygen levels so important for cell growth - correct answer Oxygen levels are tied to types of processes microbes use to produce energy. Therefore, microbes have evolved to grow within very specific oxygen concentrations Why is temperature, PH, Water Availability, Pressure:, so important for cell growth - correct answer These factors of all exert an influence on the enzymatic activity of microbial proteins, as well as on the structure of proteins found within the cells Denaturation can occur as a result of temp, pH, pressure, water availability changing away from optimal levels Obligate aerobes: - correct answer These microbes undergo aerobic respiration, in which oxygen serves as the terminal electron acceptor in the ETC facultative anaerobes - correct answer do not require oxygen for growth. However, they do grow better in its presence, as it is used as the terminal electron acceptor in the ETC for aerobic respiration (more efficient than anaerobic) and will therefore use it when it is available. Aerotolerant anaerobe: - correct answer Although these microbes can tolerate oxygen, they do not use it. As a result, they have strictly fermentative metabolism Strict anaerobes: - correct answer oxygen is toxic. They generate energy by fermentation or anaerobic respiration. Microaerophiles: - correct answer are damaged by atmospheric levels (20%) of oxygen, but still require 2-10% of atmospheric oxygen levels for growth. Toxic O2 derivatives called reactive oxygen species (ROS) can form when - correct answer cellular proteins transfer electrons to O2 ROS can - correct answer damage proteins, lipids, and nucleic acids Photosynthetic prokaryotes convert - correct answer CO2 in organic molecules, a key component of the carbon cycle